Ecosystems, Biomes & Environmental Change

Question 1

How much energy is transferred from one trophic level to the next in a food web?

Answer 1

Only 10%

Question 2

Phosphorus cycle

Answer 2

1.) As sedimentary rocks go through weathering, phosphate ions are released into soil or shallow waters

2.) Gets absorbed by the roots of the plants that need phosphate

3.) Animals eat the plants containing phosphate

4.) The phosphate is released as excrement back into the soil.

5.) Some of that soil gets into waterways and begins to settle down and form new layers of sedimentary rock.

Question 3

Oxygen cycle

Answer 3

1.) Plants go through photosynthesis, where O2 is generated

2.) It is released as part of the process

3.) O2 makes it way into the atmosphere where it is breathed by various animals

4.) Animals breathe out CO2, which goes back to the plants

Question 4

Nitrogen cycle

Answer 4

1.) Bacteria use the nitrogen in the air that is inorganic, and convert it into organic nitrogen.

2.) The organic nitrogen is then used by plants and animals

3.) Organic nitrogen remains in the plants and animals until they die

4.) When they die and are decomposed, the nitrogen is released back into the air in its inorganic form

Question 5

Relationship between rainfall and elevation

Answer 5

When clouds from the ocean move inland, they release moisture in the form of rain.

As they reach higher elevations, they release more rain. By the time they reach the far side of mountains, the moisture is almost completely depleted.

The further down the backside of the mountain they move, the less rain there is. This leaves the inland side much drier than the ocean side.